strsplit

问题 I have a dataframe with a column of strings and want to extract substrings of those into a new column. Here is some sample code and data showing I want to take the string after the final underscore character in the id column in order to create a new_id column. The id column entry always has 2 underscore characters and it's always the final substring I would like. df = data.frame( id = I(c("abcd_123_ABC","abc_5234_NHYK")), x = c(1.0,2.0) ) require(dplyr) df = df %>% dplyr::mutate(new_id =

问题 I have a table called LOAN containing column named RATE in which the observations are given in percentage for example 14.49% how can i format the table so that all value in rate are edited and % is removed from the entries so that i can use plot function on it .I tried using strsplit. strsplit(LOAN$RATE,"%") but got error non character argument 回答1: Items that appear to be character when printed but for which R thinks otherwise are generally factor classes objects. I'm also guessing htat you

问题 I'm a bit new still to using data.table and understanding all its subtleties. I've looked in the doc and in other examples in SO but couldn't find what I want, so please help ! I have a data.table which is basically a char vector (each entry being a sentence) DT=c("I love you","she loves me") DT=as.data.table(DT) colnames(DT) <- "text" setkey(DT,text) # > DT # text # 1: I love you # 2: she loves me What I'd like to do, is to be able to perform some basic string operations inside the DT object

问题 I wish to split strings at a certain character while retaining that character in the second resulting string. I can achieve almost all of the desired operation, except that I lose the characters I specify in strsplit , which I guess is called the delimiter. Is there a way to request that strsplit retain the delimiter? Or must I use a regular expression of some kind? Thank you for any advice. This seems like a very basic question. Sorry if it is a duplicate. I prefer to use base R. Here is an

问题 I wish to split strings at a certain character while retaining that character in the second resulting string. I can achieve almost all of the desired operation, except that I lose the characters I specify in strsplit , which I guess is called the delimiter. Is there a way to request that strsplit retain the delimiter? Or must I use a regular expression of some kind? Thank you for any advice. This seems like a very basic question. Sorry if it is a duplicate. I prefer to use base R. Here is an

问题 I'm looking to split a string of a generic form, where the square brackets denote the "sections" of the string. Ex: x <- "[a] + [bc] + 1" And return a character vector that looks like: "[a]" " + " "[bc]" " + 1" EDIT: Ended up using this: x <- "[a] + [bc] + 1" x <- gsub("\\[",",[",x) x <- gsub("\\]","],",x) strsplit(x,",") 回答1: I've seen TylerRinker's code and suspect it may be more clear than this but this may serve as way to learn a different set of functions. (I liked his better before I

问题 Common sense and a sanity-check using gregexpr() indicate that the look-behind and look-ahead assertions below should each match at exactly one location in testString : testString <- "text XX text" BB <- "(?<= XX )" FF <- "(?= XX )" as.vector(gregexpr(BB, testString, perl=TRUE)[[1]]) # [1] 9 as.vector(gregexpr(FF, testString, perl=TRUE)[[1]][1]) # [1] 5 strsplit() , however, uses those match locations differently, splitting testString at one location when using the lookbehind assertion, but

问题 Common sense and a sanity-check using gregexpr() indicate that the look-behind and look-ahead assertions below should each match at exactly one location in testString : testString <- "text XX text" BB <- "(?<= XX )" FF <- "(?= XX )" as.vector(gregexpr(BB, testString, perl=TRUE)[[1]]) # [1] 9 as.vector(gregexpr(FF, testString, perl=TRUE)[[1]][1]) # [1] 5 strsplit() , however, uses those match locations differently, splitting testString at one location when using the lookbehind assertion, but

问题 I have a data frame that contains a column with multiple values consisting of gene name synonyms separated by semicolons: score <- c("32.01","19.5","18.0") symbol <- c("30 kDa adipocyte complemen related protein","AAT1","Cachectin") synonym <- c("30 kDa adipocyte complemen related protein; 30 kDa adipocyte complement-related protein; ACDC; ACRP30; ADIPOQ; APM-1; APM1; Adipocyte C1Q and collagen domain containing","AAT1; AAT1; ALT-1; ALT1; Alanine aminotransferase; Alanine aminotransferase 1;

问题 I have written a for loop in which to split 5000 rows accordingly along each of the columns that they are in. Example of the cell array that contains those rows: From that picture, i would like to split each row accordingly along their respective columns of that row starting from the first column to the end. This is the code that i have written: for i = pdbindex(:,1) clean_pdb = regexprep(pdbindex, ':', ' '); % removes the colon (:) from the array and replaces it with a whitespace pdb2char =